Patients with a skin lesion suspected to be melanoma had to wait an average of 114 days from their first appointment to treatment, according to an audit carried out at Waikato Hospital.
The study, carried out by staff members at the hospital and published in today's New Zealand Medical Journal, was to determine whether the hospital could comply with aspirational cancer treatment targets suggested by the National Melanoma Standards working group in 2008.
The study found the hospital's compliance was low for all of the tough standards for timely treatment of melanoma patients although it surpassed the Government's Faster Cancer Treatment target by 1 per cent in August.
The Faster Cancer Treatment target currently requires health boards to ensure that 85 per cent of patients received their first treatment within 62 days of being found to have a high suspicion of cancer.
When looking at melanoma patients alone, none of the people treated in the Waikato in the year ending February 16, 2016, was treated within the 62 days, the study found. The average time from first suspicion of cancer to treatment was 114 days with a range of 63 to 320 days.
Once a biopsy was done by the hospital, the average wait time for treatment was 43 days with a range of eight to 223 days - 21.7 per cent of patients were treated inside the aspirational 31-day target.
One of the authors of the study, and a plastic and reconstructive surgeon at Waikato Hospital, Dr Brandon Adams said the part of the difference was in the definitions of "first treatment".
The Government's targets were satisfied with the removal of the cancer on the skin while the aspirational targets required the treatment of lymph nodes as well during the time-frame, he said.
Some skin cancers were also not included in the current Government target, Adams said.
While the hospital was not able to achieve more than 43 per cent on any of the aspirational targets, work was under way to improve that.
A change in the way referrals were graded put pressure on cancer services during the period of the trial, Adams said, but since then a new unit had been opened with two new senior staff members to manage the skin clinic.
The authors of the report said it was unlikely patients suffered any negative effect from the wait, although Adams admitted it would have been a stressful time for them.
The authors said the main focus to improve compliance should be in logistics.
But University of Otago plastic surgeon Dr Jeremy Simcock said in an editorial published in today's journal that he disagreed there was no harm caused by the delay.
"While clear evidence of harm from delayed diagnosis and treatment of melanoma is currently lacking, other tumour streams evidence suggests timely management improves outcomes."
He also said it was probable that prolonging the interval between raising a suspicion of cancer and treatment increased patients' distress and reduced their quality of life.
It was important health boards start to measure themselves against the aspirational standards in an effort to make sure they were providing the best care for patients, Simcock said.